Telephone-receiver.



H. W. SULLIVAN.

TELEPHONE RECEIVER. APPLIOA'TION 11.31) Novso, 1907.

Patented Feb. 2, 1909.

/ A ztor neys.

Witnesses piece 2.

TELEPHONE-EECEIVEE.

Specification of Letters Patent.

Patented Feb. 2, 1909.

Application filed. November 30, 1907. Serial No. 404:,535.

To all whom it ma concern:

Be it known hilztt I, HERBERT WATsoN SULIWAN, a subject of the King of Great Britain and lrcland, and a resident of Lonhave invented an Improvement in TQlCpllOl'lB-liGCGlVfllS, of which the following specification.

The object of my invention is to improve tel cphone receiver. of the kind which are carried upon a head support.

Another object of my inventionis to prevent injury to the windings of the magnet by high tension currents, such means being protected from mechanical injury.

I attain these objects by the mechanism illustrated in the accompanying drawings,

in which,-

Figure 1 is a side elevation of a telephone receiver embodying my invention. Fig. 2 is a front view on an enlarged scale with the ear piece and diapl'iragm removed. Fig. 3' is a section on the line of Fig. 2-. Fig. 4 is a section on the line 4- of Fig. 2. Fig. 5 is a detail view of a mechanism for producing the spark gap; and Fig. 6 is an elevation partly in section of a inodilied form of receiver. 4

in all of the views like parts are desi'gi'ilited by the same reference characters.

The receiver coin a casing 1, which may he of any suitaole material, with an ear The magnets 8 lie within the casing, and are mechanically connected to the annular pole-piece 4-. This annular pole-piece 4 lies wit in the casing, which latter is preferably cylindrical, as shown. 'lhebolts 5 pass through that wall oi the casing opposite the ear piece, and mechanically connect -with the annular pole-piece 4i, but are -lectrically insulated therefrom by the sleeves 6. The bolts outside of the casing are provided with connections, as shown, for the wires 7',

in the usual manner.

T he spark gap is shown as produced by which he substannicans oi the screws 8- 0 tially parallcl to one another, but a sullicient distance apart so as to produce the gap. Each screw carried upon an arm is pivoted upon the inner end of the bolt/5 by means oi a screw l0. The free end of the a w is bent up, as shown, provided with a central opening, through which passes the screw 8.

arms are held rigidly in position; by loosen ing tlwna, each arm may he swung upon its pivot, and the screws may be adjusted j toward or awa T from each other.

. connected to the arm 4 by 9, which 3y tightening the screws 10 the lei" disn'mntling or partly The arms 9 are electrical y connected with the bolts 5, and are provided will flexible connections 11 to the coils of the magnets 3. It will be apparent from this arrangement, as shown in Fig. 2, that the spark gap produced by the screws 8-8 is in shunt with the coils of the magnet. The extent of separation of the parts producing the gap may be adjusted,

and as all parts lie within the casing they are protected from mechanical injury. The

screws 8-8 serve as a convenient means for producing a s ark gap with multiple points, each thread 0 the screw constituting a point.- The screws also have an advantage in that when the sharp edge .of the thread becomes roughened by the passage of sparks across the gap, the screw may be given a partial turn, and another part or' the thread will be brought into position to form the spark gap. The receiver is so mounted u on the head support that it may be adjuste in any osition, vertical, horizontal or any interrn'e iate plane, to readily accommodate itsclfto the ear of the operator. To secure this desirable result, the casing 1 is carried upon the arm 12 by a ball and socket joint. The arm 12'is connectcd to the head sup iio'rting bands l3-14 by means of the usua bolt,.the ends of the bands having slots so as to adjust them to rest upon heads of different sizes. Tinend of the arm 12 has a hole in it which rests against the ball 15, such hall being attached to that side of the casing 1 opposite the ear piece. The opening in the arm 12 of less diameter than the ball, as shown inFigs. 3 impossible to remove the .moved from the casing.

For the purpose of completing the joint, a plate 16 is Pl'O'VldtEtl, such plate being provided with an opening also smaller than the ball. This pl ate is shown in. the drawings as an adjiv g screw 17. By means of tni: s'crcv: the plate 16 can be moved toward the arm 12 and the ball pressed between them, the plate alwayalying upon one side oi the larget diameter of the ball, and the arm always lying upon the other side. An additional screw l8 may be provided for holding the plate in position upon the arm.

For the purpmc cl admit i log the ready application ol the adha'tohlisupport to c: ing telephone receivers u all-cut the news:

In accordance with the provisions of the patent statutes, I have described the prinei ple of my invention, together with the apps-- ratus which I now consider to re 'n'esent the best embodiment thereof, but desire to have it understood that the apparatus shown is merely illustrative'and that the invention can be carried out in other ways.

Having now described my invention, What I claim as new and desire to secure by Letters Patent, is

1. A telephone receiver having a spark gap .in shunt with the magnets and located within the raisin? 2. A te ephone receiver having a multiple point spark gap in shunt with the magnets and within t e casing.

I 3. A telephone receiver having aspark gap in shunt with magnets and within the casing, I said gap being adjustable as to distance of I separation.

i 4. A telephone receiver having a spark gap 1' in shunt with the magnets and within the casing, said gap being formed with screws 4 lying substantiall parallel and separated by I an interval producing the gap.

l 5. A telephonereceiver hnvinp in combil nation the operating magnets and the casing, l with arms pivoted within the casing, means I for adjusting the position of the arms and screws on the free ends oi the arms, the said screws lying substantially parallel to one another and constitutinga spark gap.

This specification signed and witnessed this 19th day of November, 1907.

HERBERT WATSON SULLIVAN. Witnesses:

B. WELLAND, F. L. RAND. 

